Mesenteric venous thrombosis

MVT is a clot that blocks blood flow in a mesenteric vein. There are two such veins through which blood leaves the intestine. The condition stops the normal blood circulation of the intestine and can result in damage to the intestine.

The exact cause of MVT is unknown. However, there are many diseases that can lead to MVT. Many of the diseases cause swelling (inflammation) of the tissues surrounding the veins, and include:

• Appendicitis
• Cancer of the abdomen
• Diverticulitis
• Liver disease with cirrhosis
• High blood pressure in the blood vessels of the liver
• Abdominal surgery or trauma
• Pancreatitis
• Inflammatory bowel disorders (Crohn disease and ulcerative colitis)
• Heart failure

People who have disorders that make the blood more likely to stick together (clot) have a higher risk for MVT and include:

• Protein C or S deficiencies
• Polycythemia vera
• Essential thrombocythemia

Birth control pills and estrogen medicines also increase risk.

MVT is more common in men than women. It mainly affects middle aged or older adults.

Mesenteric venous thrombosis (MVT) is a blood clot in one or more of the major veins that drain blood from the intestine. The superior mesenteric vein is most commonly involved.

A CT scan is the main test used to diagnose MVT.

Other tests may include:

• Angiogram (studying the blood flow to the intestine)
• MRI of the abdomen
• Ultrasound of the abdomen and mesenteric veins

The outlook depends on the cause of the thrombosis and any damage to the intestine. Getting treatment for the cause before the intestine has died can result in a good recovery.

Intestinal ischemia is a serious complication of MVT. Part or all of the intestine dies because of poor blood supply.

Cloud A, Dussel JN, Webster-Lake C, Indes J. Mesenteric ischemia. In: Yeo CJ, ed. Shackelford's Surgery of the Alimentary Tract. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 87.

Feuerstadt P, Brandt LJ. Intestinal ischemia. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 118.

Roline CE, Reardon RF. Small intestine. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 78.

Schafer AI. Approach to the patient with bleeding or thrombosis. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 157.

Symptoms may include any of the following:

• Abdominal pain, which may get worse after eating and over time
• Bloating
• Constipation
• Bloody diarrhea
• Fever
• Septic shock
• Lower gastrointestinal bleeding
• Vomiting and nausea

Blood thinners are used to treat MVT when there is no associated bleeding. In some cases, medicine can be delivered directly into the clot to dissolve it. This procedure is called thrombolysis.

Less often, the clot is removed with a type of surgery called thrombectomy.

If there are signs and symptoms of a severe infection called peritonitis, surgery to remove the injured part of the intestine is done. After surgery, an ileostomy (opening from the small intestine into a bag on the skin) or colostomy (an opening from the colon into the skin) may be needed.

Contact your health care provider if you have severe or repeated episodes of abdominal pain.